# encoding: utf-8

import pygame

import sys

import random

# 全局定义

SCREEN_X = 600

SCREEN_Y = 600


# 蛇类

# 点以25为单位

class Snake(object):

    # 初始化各种需要的属性 [开始时默认向右/身体块x5]

    def __init__(self):

        self.dirction = pygame.K_RIGHT

        self.body = []

        for x in range(5):
            self.addnode()

            # 无论何时 都在前端增加蛇块

    def addnode(self):

        left, top = (0, 0)

        if self.body:
            left, top = (self.body[0].left, self.body[0].top)

        node = pygame.Rect(left, top, 25, 25)

        if self.dirction == pygame.K_LEFT:

            node.left -= 25

        elif self.dirction == pygame.K_RIGHT:

            node.left += 25

        elif self.dirction == pygame.K_UP:

            node.top -= 25

        elif self.dirction == pygame.K_DOWN:

            node.top += 25

        self.body.insert(0, node)

        # 删除最后一个块

    def delnode(self):

        self.body.pop()

        # 死亡判断

    def isdead(self):

        # 撞墙

        if self.body[0].x not in range(SCREEN_X):
            return True

        if self.body[0].y not in range(SCREEN_Y):
            return True

            # 撞自己

        if self.body[0] in self.body[1:]:
            return True

        return False

        # 移动！

    def move(self):

        self.addnode()

        self.delnode()

        # 改变方向 但是左右、上下不能被逆向改变

    def changedirection(self, curkey):

        LR = [pygame.K_LEFT, pygame.K_RIGHT]

        UD = [pygame.K_UP, pygame.K_DOWN]

        if curkey in LR + UD:

            if (curkey in LR) and (self.dirction in LR):
                return

            if (curkey in UD) and (self.dirction in UD):
                return

            self.dirction = curkey

        # 食物类


# 方法： 放置/移除

# 点以25为单位

class Food:

    def __init__(self):

        self.rect = pygame.Rect(-25, 0, 25, 25)

    def remove(self):

        self.rect.x = -25

    def set(self):

        if self.rect.x == -25:

            allpos = []

            # 不靠墙太近 25 ~ SCREEN_X-25 之间

            for pos in range(25, SCREEN_X - 25, 25):
                allpos.append(pos)

            self.rect.left = random.choice(allpos)

            self.rect.top = random.choice(allpos)

            print(self.rect)


def show_text(screen, pos, text, color, font_bold=False, font_size=60, font_italic=False):
    # 获取系统字体，并设置文字大小

    cur_font = pygame.font.SysFont("宋体", font_size)

    # 设置是否加粗属性

    cur_font.set_bold(font_bold)

    # 设置是否斜体属性

    cur_font.set_italic(font_italic)

    # 设置文字内容

    text_fmt = cur_font.render(text, 1, color)

    # 绘制文字

    screen.blit(text_fmt, pos)


def main():
    pygame.init()

    screen_size = (SCREEN_X, SCREEN_Y)

    screen = pygame.display.set_mode(screen_size)

    pygame.display.set_caption('Snake')

    clock = pygame.time.Clock()

    scores = 0

    isdead = False

    # 蛇/食物

    snake = Snake()

    food = Food()

    while True:

        for event in pygame.event.get():

            if event.type == pygame.QUIT:
                sys.exit()

            if event.type == pygame.KEYDOWN:

                snake.changedirection(event.key)

                # 死后按space重新

                if event.key == pygame.K_SPACE and isdead:
                    return main()

        screen.fill((255, 255, 255))

        # 画蛇身 / 每一步+1分

        if not isdead:
            scores += 1

            snake.move()

        for rect in snake.body:
            pygame.draw.rect(screen, (20, 220, 39), rect, 0)

            # 显示死亡文字

        isdead = snake.isdead()

        if isdead:
            show_text(screen, (100, 200), 'YOU DEAD!', (227, 29, 18), False, 100)

            show_text(screen, (150, 260), 'press space to try again...', (0, 0, 22), False, 30)

            # 食物处理 / 吃到+50分

        # 当食物rect与蛇头重合,吃掉 -> Snake增加一个Node

        if food.rect == snake.body[0]:
            scores += 50

            food.remove()

            snake.addnode()

            # 食物投递

        food.set()

        pygame.draw.rect(screen, (136, 0, 21), food.rect, 0)

        # 显示分数文字

        show_text(screen, (50, 500), 'Scores: ' + str(scores), (223, 223, 223))

        pygame.display.update()

        clock.tick(10)


if __name__ == '__main__':
    main()

